What Are Students Thinking When They Pick Their Answer?Michael J. Sanger and Amy J. Phelps330 students were asked to answer a multiple-choice question concerning gas properties at the microscopic level and explain their reasoning. Of those who selected the correct answer, 80% provided explanations consistent with the scientifically accepted answer, while 90% of the students who picked an incorrect choice provided explanations with at least one misconception.Sanger, Michael J.; Phelps, Amy J. J. Chem. Educ.2007, 84, 870.

Gases |

Kinetic-Molecular Theory |

Phases / Phase Transitions / Diagrams |

Qualitative Analysis

On the Buoyancy of a Helium-Filled BalloonJohn E. HarrimanIt is shown by expansion of the exponential in the barometric formula that the forces due to pressure acting on a balloon are of the form (PV/RT)Mg and that results agree with those suggested by Archimedes principle. Einstein's equivalence principal provides an answer to what balloons will do in an accelerated car. Harriman, John E. J. Chem. Educ.2005, 82, 246.